CN213242596U

CN213242596U - Sensor array

Info

Publication number: CN213242596U
Application number: CN202022493890.8U
Authority: CN
Inventors: 张珽; 陆骐峰; 孙富钦; 王子豪
Original assignee: Suzhou Institute of Nano Tech and Nano Bionics of CAS
Current assignee: Suzhou Institute of Nano Tech and Nano Bionics of CAS
Priority date: 2020-11-02
Filing date: 2020-11-02
Publication date: 2021-05-18
Anticipated expiration: 2030-11-02

Abstract

The utility model provides a sensor array, which comprises a flexible substrate, a first electrode layer, a first protective layer, a second electrode layer and a sensing layer which are arranged in sequence; the second electrode layer comprises a first adhesion layer, a transition layer, a second adhesion layer and an electrode protection layer which are sequentially arranged. The sensor array has the advantages of high density, high signal sensing sensitivity, low failure rate and the like through the special design of the structure, provides a new idea for the design and preparation of the sensor array, and has important significance.

Description

Sensor array

Technical Field

The utility model belongs to the technical field of the sensor, concretely relates to sensor array.

Background

With the development of science and technology and the continuous improvement of the modernization level, the demand level of people for health care and intelligent interaction is higher and higher; in the field of medical health, physiological indexes such as heartbeat, pulse, blood pressure, respiration and the like are acquired in a wearable, applicable or even implantable mode and the like, so that the method is a common method for monitoring the health level at present, and the accuracy of detection signals, the biological safety of implanted equipment and the wearing comfort become the most concerned problems for people; therefore, in the applications in the fields of health care, human-computer interaction and the like, the sensor has to have better flexibility to adapt to various actions, and also has to be capable of sensing parameters such as pressure, humidity, temperature and the like so as to adjust the self state by identifying various environmental information and complete various complex tasks.

The flexible sensor is a focus of research in the field of sensors at present because the used materials are nontoxic and harmless and can be compatible with flexible systems such as organisms and the like. CN210774448U discloses a flexible pressure sensor, which includes a flexible substrate, on which a pressure sensor array is disposed; the pressure sensor array comprises a plurality of pressure sensing chips which are uniformly distributed on a substrate, a row electrode array and a column electrode array are further arranged on the substrate, the row electrode array comprises row electrodes which are in one-to-one correspondence with the pressure sensing chips, the column electrode array comprises column electrodes which are in one-to-one correspondence with the pressure sensing chips, and each pressure sensing chip is respectively connected with one row electrode and one column electrode; the flexible pressure sensing device further comprises a flexible coating layer for coating the substrate, the pressure sensing chip, the row electrode array and the column electrode array. The flexible pressure sensor array can test pressure change on one surface or one line, and can acquire pressure distribution conditions along the blood flow direction or in a local area, so that more pulse test information can be acquired, and besides the pulse beating frequency, blood flow information can be acquired, and more test information can be provided for cardiovascular diseases and the like. CN108458819A discloses a large-area flexible pressure sensor, which sequentially comprises a flexible electrode substrate, a composite pressure-sensitive layer, an insulating adhesive layer and a flexible substrate, wherein a first electrode array and a second electrode array are prepared on the flexible electrode substrate, and any point electrode of the first electrode array corresponds to a point electrode of the second electrode array one by one to serve as an electrode group; the composite pressure-sensitive layer is a pressure-sensitive layer dot matrix, and each pressure-sensitive layer dot unit directly prints uncured pressure-sensitive composite materials on the corresponding electrode group in a screen printing mode and then cures to form and completely cover the corresponding electrode group. The sensor array with large area can be realized, the pressure-sensitive array and the electrode array have better connectivity, better adhesive force, smaller volume and higher preparation efficiency, and the process of repeatedly installing the pressure-sensitive layer is avoided. CN105117052A discloses a flexible sensor array, which includes a flexible substrate, an array electrode, a flexible sensitive layer and a protective layer; the array electrode is arranged on the surface of the flexible substrate, wherein the array electrode comprises at least one electrode array; the surface of the array electrode is also provided with a flexible sensitive layer; the protective layer is arranged above the flexible sensitive layer and covers the flexible sensitive layer and the flexible substrate. By arranging the array electrode comprising at least one electrode array between the flexible substrate and the flexible sensitive layer, each electrode array can independently acquire pressure data, thereby realizing the technical effect of simultaneously acquiring multipoint pressure data. Although the flexible sensor array is successfully prepared in the prior art, on one hand, the problem that the whole sensor array fails due to damage of a single device often occurs when the flexible sensor array is used because the electrode density of the sensor array is not enough, and on the other hand, the sensing sensitivity of the sensor array in the prior art to signals needs to be improved.

Therefore, it is a problem that research is required to develop a sensor array with high density, low failure rate and high signal sensing sensitivity.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to provide a sensor array, sensor array is provided with flexible substrate, electrode layer, protective layer and sensing layer, and right the electrode layer carries out multilayer metal structure's design, makes sensor array has advantages such as high density, high sensitivity, low inefficacy, can realize the sensing function to signals such as sound, gas, light.

In order to achieve the purpose of the utility model, the utility model adopts the following technical proposal:

the utility model provides a sensor array, which comprises a flexible substrate, a first electrode layer, a first protective layer, a second electrode layer and a sensing layer which are arranged in sequence;

the second electrode layer comprises a first adhesion layer, a transition layer, a second adhesion layer and an electrode protection layer which are sequentially arranged.

The utility model provides a sensor array's section structure sketch map and planar structure sketch map are shown as figure 1 and figure 2 respectively: wherein 1 represents a flexible substrate; 2 represents a first electrode layer arranged on the flexible substrate 1, the secondary sensing units of the sensor array are formed by the gear shaping electrodes in the first electrode layer 2; 3 represents the first protection layer, a schematic plan structure diagram of the first protection layer 3 is shown in fig. 3, a black surrounding area is hollowed out, so that the gear shaping electrode and the corresponding connecting wire in the first electrode layer 2 are leaked out; 4 represents a second electrode layer, and a schematic cross-sectional structure and a schematic plan structure of the second electrode layer are shown in fig. 4 and fig. 5, wherein 4-1 represents a first adhesive layer, 4 represents a first adhesive layer connected with a first protective layer 3, 4-2 represents a transition layer, 4-3 represents a second adhesive layer, and 4-4 represents an electrode protective layer; the second electrode layer and the first electrode layer 2 are mutually crossed to form a main sensing unit of the sensor array; 5 represents a sensing layer; the composite structural design of the main sensing unit and the secondary sensing unit can effectively solve the problem of failure of the whole sensor device caused by short circuit or open circuit at a certain position of the sensing layer 5; secondly, the utility model provides a second electrode layer 4 among the sensor array includes the first adhesion layer, transition layer, second adhesion layer and the electrode protection layer that set gradually, and wherein, first adhesion layer hugs closely first protection layer 3, adopts the design of this kind of multilayer metal structure, and first adhesion layer and flexible substrate have fine adhesion, increase the stability of second electrode layer; the transition layer has better mechanical property and is not easy to break at the step; the second adhesion layer has good adhesion, so that the stability of the second electrode layer is improved; the electrode protection layer has good chemical stability, and the chemical stability of the second electrode layer can be improved; sufficient supporting force exists between layers of the second electrode layer, the problem that the surface is not flat during preparation of the sensor array or the problem of lead fracture caused by overlarge gradient of a first protection layer hollow window during the process of relieving bending deformation and interconnecting a gear shaping electrode and the second electrode layer in the first electrode layer during use of the sensor array can be effectively solved. Through the above-mentioned special design to sensor array structure, make sensor array has signal perception sensitivity height and the inefficiency advantage such as.

Preferably, the flexible substrate has a thickness of 0.5-20 μm, such as 1.5 μm, 2 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm, 15 μm, 3.5 μm, 5 μm, 6.5 μm, 7 μm, 8.5 μm, 9 μm, 10.5 μm, 12 μm, 13.5 μm, 15 μm, 17.5 μm, or 19 μm, and the specific point values between the above point values are limited to space and are not exhaustive, and the present invention is not exhaustive.

Preferably, the thickness of the first electrode layer is 50nm to 200nm, such as 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, 100nm, 105nm, 110nm, 115nm, 120nm, 125nm, 130nm, 135nm, 140nm, 145nm, 150nm, 160nm, 170nm, 180nm or 190nm, and the specific values therebetween are limited to space and for the sake of brevity, and the present invention does not exhaust the specific values included in the range.

Preferably, the first electrode layer includes a gear shaping electrode and a wire.

Preferably, the connection mode between the gear shaping electrodes is in series connection and/or parallel connection.

The utility model provides a planar structure schematic diagram of first electrode layer is shown in FIG. 6: wherein, 2-1 represents a gear shaping electrode, and 16 gear shaping electrodes 2-1 are connected in series to form a 4 x 4 secondary sensing unit; 2-2 represents a lead, and the lead 2-2 and the second electrode layer of the present invention constitute a 10 × 10 main sensing unit; the design of a plurality of secondary sensing units and a main sensing unit realizes that the problem of failure of the whole sensor array caused by damage of a single site in a high-density sensor array is effectively solved on the premise of high resolution.

Preferably, the gear shaping electrode comprises a chromium layer and a gold layer, the thickness of the chromium layer is 5-15 nm, such as 6nm, 7nm, 8nm, 9nm, 10nm, 11nm, 12nm, 13nm or 14nm, and the specific values between the above values are limited by space and for the sake of brevity, the present invention does not provide an exhaustive list of the specific values included in the range.

Preferably, the thickness of the gold layer is 45-100 nm, such as 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm or 95nm, and the specific values therebetween are limited to the space and for the sake of brevity, and the present invention is not exhaustive of the specific values included in the range.

Preferably, a second protective layer is further disposed between the second electrode layer and the sensing layer.

Preferably, the thicknesses of the first protective layer and the second protective layer are each independently 0.5 to 3 μm, such as 0.5 μm, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, or 3 μm, and specific point values therebetween are limited to space and for the sake of brevity, and the present invention does not exhaustive list the specific point values included in the range.

The utility model provides a have the fretwork position in the first protective layer, wherein the slope of fretwork position is less than 10, can make sensor array has lower failure degree.

Preferably, the thickness ratio of the second electrode layer to the first protective layer is 1 (2-10), such as 1:2.2, 1:2.4, 1:2.6, 1:2.8, 1:3, 1:3.2, 1:3.4, 1:3.6, 1:4, 1:5, 1:6, 1:7, 1:8, or 1: 9.

Preferably, the first adhesive layer has a thickness of 10-20 nm, such as 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm or 20nm, and the specific values therebetween are limited by space and for brevity, the present disclosure is not exhaustive of the specific values included in the range.

Preferably, the thickness of the transition layer is 200-500 nm, 420nm, 440nm, 460nm, 480nm, 500nm, 520nm, 540nm, 560nm, 580nm, 600nm, 620nm, 640nm, 660nm, 680nm, 700nm, 720nm, 740nm, 760nm, 780nm, 800nm, 820nm, 840nm, 860nm or 880nm, and the specific values therebetween are limited to space and for the sake of brevity, and the present invention does not exhaust the specific values included in the range.

Preferably, the first adhesion layer is a chromium layer or a titanium layer.

Preferably, the transition layer is a copper layer or an aluminum layer.

Preferably, the thickness of the second adhesive layer is 10-230 nm, 12nm, 14nm, 16nm, 18nm, 20nm, 50nm, 70nm, 90nm, 110nm, 130nm, 150nm, 170nm, 210nm or 220nm, and the specific values therebetween are limited to the space and for the sake of brevity, and the present invention is not exhaustive.

Preferably, the thickness of the electrode protection layer is 20-100 nm, such as 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm or 95nm, and the specific values therebetween are limited by space and for the sake of brevity, and the present invention is not exhaustive.

Preferably, the second adhesion layer is a chromium layer or a titanium layer.

Preferably, the electrode protection layer is a gold layer or a platinum layer.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model provides a sensor array comprises a flexible substrate, a first electrode layer, a first protective layer, a second electrode layer and a sensing layer which are arranged in sequence; the second electrode layer comprises a first adhesion layer, a first transition layer, a second adhesion layer and an electrode protection layer which are sequentially arranged, and the sensor array is high in stability, low in failure rate lower than 1% and 60 mu m in resolution ratio through special design of the sensor array structure; the failure rate of the sensor array with a non-multilayer metal structure is 90%, and the stability is poor, so that the second electrode layer structure with the multilayer metal structure is beneficial to improving the stability of the device and reducing the failure rate of the array; secondly, use secondary sensing unit and the compound array structure design scheme of main sensing unit to and the gear shaping electrode that the tandem system connects helps improving sensing unit density as secondary sensing unit, and prior art's the resolution ratio that provides the second sensor array is 1mm, explains sensor array has advantages such as high density, high sensitivity and low failure rate concurrently, provides a new thinking for preparing high density, multi-modal and integrated sensor array, has important meaning.

Drawings

Fig. 1 and fig. 2 are schematic structural diagrams of a section and a plane of a sensor array provided by the present invention, respectively;

FIG. 3 is a schematic plan view of a first passivation layer;

FIGS. 4 and 5 are schematic views of cross-sectional and planar structures, respectively, of the second electrode layer;

FIG. 6 is a schematic plane structure diagram of the first electrode layer;

fig. 7 is a schematic cross-sectional structure diagram of a sensor array provided in embodiment 1.

The sensor comprises a flexible substrate 1, a first electrode layer 2, a gear shaping electrode 2-1, a lead 2-2, a first protective layer 3, a second electrode layer 4, a first adhesive layer 4-1, a transition layer 4-2, a second adhesive layer 4-3, an electrode protective layer 4-4, a sensing layer 5 and a second protective layer 6.

Detailed Description

The technical solution of the present invention will be further explained by the following embodiments. It should be understood by those skilled in the art that the described embodiments are merely provided to assist in understanding the present invention and should not be construed as specifically limiting the present invention.

Example 1

A schematic cross-sectional structure of a sensor array is shown in FIG. 7, wherein 1 is a flexible substrate, 2 is a first electrode layer, 3 is a first protective layer, 4 is a second electrode layer, 5 is a sensing layer, and 6 is a second protective layer; the schematic cross-sectional structure of the second electrode layer 4 is shown in fig. 4, 4-1-the first adhesion layer, 4-2-the transition layer, 4-3-the second adhesion layer, 4-4-the electrode protection layer;

wherein, the flexible substrate 1 is a polyimide layer (PI layer) with the thickness of 15 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 10nm, the thickness of the gold layer is 60nm, and the formed gear shaping electrodes are connected in series to form a secondary sensing unit; the first protective layer 3 is a PI layer with the thickness of 2 mu m, and the second electrode layer 4 is a chromium layer/copper layer/chromium layer/gold layer with the thickness of 20nm, 500nm, 30nm and 100nm in sequence; the second protective layer 6 is a PI layer with the thickness of 2 mu m; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 10mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using Polydimethylsiloxane (PDMS)).

Example 2

A sensor array is shown in a schematic cross-sectional structure of FIG. 1, wherein 1 is a flexible substrate, 2 is a first electrode layer, 3 is a first protective layer, 4 is a second electrode layer, and 5 is a sensing layer; the schematic cross-sectional structure of the second electrode layer 4 is shown in fig. 4, 4-1-the first adhesion layer, 4-2-the transition layer, 4-3-the second adhesion layer, 4-4-the electrode protection layer;

wherein, the flexible substrate 1 is a polyimide layer (PI layer) with the thickness of 15 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 10nm, the thickness of the gold layer is 60nm, and the formed gear shaping electrodes are connected in series to form a secondary sensing unit; the first protective layer 3 is a PI layer with the thickness of 2 mu m, and the second electrode layer 4 is a chromium layer/copper layer/chromium layer/gold layer with the thickness of 20nm, 500nm, 30nm and 100nm in sequence; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 10mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using Polydimethylsiloxane (PDMS)).

Example 3

The cross-sectional structure of the sensor array and the cross-sectional structure of the second electrode layer are the same as those of embodiment 1;

wherein, the flexible substrate 1 is a polyimide layer (PI layer) with the thickness of 20 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 15nm, the thickness of the gold layer is 100nm, and the formed gear shaping electrodes are connected in series to form a secondary sensing unit; the first protective layer 3 is a PI layer with the thickness of 3 mu m, and the second electrode layer 4 is a chromium layer/copper layer/chromium layer/gold layer with the thickness of 30nm, 900nm, 40nm and 100nm in sequence; the second protective layer 6 is a PI layer with the thickness of 3 mu m; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 15mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using PDMS).

Example 4

wherein, the flexible substrate 1 is a polyimide layer (PI layer) with the thickness of 0.5 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 5nm, the thickness of the gold layer is 45nm, and the formed gear shaping electrodes are connected in series; the first protective layer 3 is a PI layer with the thickness of 3 mu m, and the second electrode layer 4 is a chromium layer/copper layer/chromium layer/gold layer with the thickness of 10nm, 400nm, 10nm and 50nm in sequence; the second protective layer 6 is a PI layer with the thickness of 0.5 mu m; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 20mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using PDMS).

Comparative example 1

A sensor array comprises a flexible substrate 1, a first electrode layer 2, a first protective layer 3, a second electrode layer 4, a sensing layer 5 and a second protective layer 6, wherein the second electrode layer 4 comprises a chromium layer and a gold layer which are sequentially arranged;

wherein the flexible substrate 1 is a PI layer, and the thickness is 15 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 10nm, the thickness of the gold layer is 60nm, and the formed gear shaping electrodes are connected in series to form a secondary sensing unit; the first protective layer 3 is a PI layer with the thickness of 2 mu m, and the second electrode layer 4 is a chromium layer/gold layer with the thickness of 20nm and 60nm in sequence; the second protective layer 6 is a PI layer with the thickness of 2 mu m; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 20mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using PDMS).

Comparative example 2

A sensor array comprises a flexible substrate, a first electrode layer, a first protective layer, a second electrode layer, a second protective layer and a sensing layer which are sequentially arranged;

wherein, the flexible substrate 1 is a polyimide layer (PI layer) with the thickness of 15 μm; the first electrode layer 2 is a chromium layer/gold layer, the thickness of the chromium layer is 10nm, the thickness of the gold layer is 60nm, a single formed gear shaping electrode is used as a secondary sensing unit, the first protective layer 3 is a PI layer, the thickness of the PI layer is 2 micrometers, and the second electrode layer 4 is a chromium layer/copper layer/chromium layer/gold layer, and is 20nm, 500nm, 30nm and 100nm sequentially; the second protective layer 6 is a PI layer with the thickness of 2 mu m; the sensing layer 5 is a thin film pressure sensor layer (obtained by coating 10mg of carbon nanotubes on a silicon template with a microstructure and performing replica molding by using PDMS).

And (3) performance testing:

(1) failure rate and stability: sequentially testing the current of each sensing unit in the 10 x 10 array by using an Agilent B1500A semiconductor parameter analyzer, and judging as failure if the open circuit or the resistance is lower than 100 ohms;

(2) sensitivity: applying pressure (weight) from small to large on any unit of the 10 x 10 array device, and testing the current change of the unit before and after applying the pressure by using an Agilent B1500A semiconductor parameter analyzer to judge the sensitivity of the unit;

the sensor arrays obtained in examples 1 to 4 and comparative examples 1 to 2 were tested by the above-mentioned test method, and the test results are shown in table 1:

TABLE 1

As can be seen from the data in table 1:

the sensor array provided by the utility model has higher stability and resolution ratio, and has lower failure rate, specifically, the second electrode layer of the sensor array provided by the embodiments 1-4 adopts a multilayer metal structure, the failure rate is lower than 1%, and the resolution ratio is 60 μm; the failure rate of the sensor array provided in the prior art (comparative example 1) is 90%, which shows that the second electrode layer of the multilayer metal structure is beneficial to improving the stability of the device and reducing the failure rate of the array; secondly, the secondary sensing unit that the gear shaping electrode series connection mode in the first electrode layer constitutes compares and regards the resolution ratio of the sensor array that single gear shaping electrode regarded as secondary sensing unit (comparative example 2) to constitute as prior art as 1mm, demonstrates the utility model provides a sensor array has the high resolution to have the lower possibility of array failure.

The applicant states that the present invention describes a structure of a sensor array through the above embodiments, but the present invention is not limited to the above embodiments, that is, the present invention does not mean that the present invention must rely on the above embodiments to be implemented. It should be clear to those skilled in the art that any improvement of the present invention is to the equivalent replacement of the selected raw materials, the addition of auxiliary components, the selection of specific modes, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A sensor array is characterized by comprising a flexible substrate, a first electrode layer, a first protective layer, a second electrode layer and a sensing layer which are sequentially arranged;

2. The sensor array of claim 1, wherein the flexible substrate has a thickness of 0.5-20 μm.

3. The sensor array of claim 1, wherein the first electrode layer has a thickness of 50-200 nm.

4. The sensor array of claim 1, wherein the first electrode layer comprises a plurality of gear teeth electrodes and a plurality of wires, and the gear teeth electrodes are connected in series and/or in parallel.

5. The sensor array of claim 4, wherein the gear shaping electrode comprises a combination of a chromium layer and a gold layer; the thickness of the chromium layer is 5-15 nm; the thickness of the gold layer is 45-100 nm.

6. The sensor array of claim 1, wherein a second protective layer is further disposed between the second electrode layer and the sensing layer.

7. The sensor array of claim 6, wherein the first protective layer and the second protective layer each independently have a thickness of 0.5-3 μm.

8. The sensor array of claim 1, wherein the thickness ratio of the second electrode layer to the first protective layer is 1 (2-10).

9. The sensor array of claim 1, wherein the first adhesion layer is a chromium layer or a titanium layer; the thickness of the first adhesion layer is 10-20 nm; the transition layer is a copper layer or an aluminum layer; the thickness of the transition layer is 200-500 nm.

10. The sensor array of claim 1, wherein the second adhesion layer is a chromium layer or a titanium layer; the thickness of the second adhesion layer is 10-30 nm; the electrode protection layer is a gold layer or a platinum layer; the thickness of the electrode protection layer is 20-100 nm.